Crusher



' J. M. A. BRIZON MayI Z, 1970 1 cRUsHEn Filed April 10. 1967 United States Patent 3,511,447 CRUSHER Jean Marie Annie Brizon, 64 Rue Ampere, Paris, France Filed Apr. 10, 1967, Ser. No. 629,722 Claims priority, application6France, Apr. 13, 1966,

Int. Cl. B02 17/16 US. Cl. 241-172 Claims ABSTRACT OF THE DISCLOSURE My invention has for its object improvements in crushers of the type including a container of a cylindrical shape provided with vertical terminal covers and along the horizontal axis of which there extends a horizontal rotary shaft carrying agitating arms of a rounded cross-section lying along radii of the cylindrical container, while the free volume of said container is almost com letely filled with small balls of a diameter of a few millimeters. The rectilinear generating lines of the cylindrical container are shorter than its radius and consequently the container is comparable in shape with a flat cell with a horizontal axis.

My present invention has for its object in particular to allow a continuous operation of the crusher through whidh a continuous throughput of the material to be crushed is caused to pass out of a feeding duct so as to be removed in a crushed condition by an output duct.

A first object of my invention is however applicable as well in the case of an intermittent operation, the apparatus being then loaded with a mass of material to be crushed, which mass is fed into it through a suitable opening which is closed thereafter, the apparatus being emptied after a predetermined duration of operation.

Said first object consists in that the agitating arms revolve with the shaft within the single fiat cell or each of the flat cells forming the crusher and are set in a manner such that their axes lie in a common radial plane and their size is selected so as to leave between said arms and the vertical walls of the cells and also between their ends and the cylindrical wall of the container narrow gaps which it is of advantage to reduce to a magnitude of 2 or 3 times the diameter of the balls filling the container.

Preferably, each flat cell carries two agitating arms extending in alignment along a common diameter of the cell.

Now, I have found that it is possible to perform thus within a comparatively narrow short time and with a comparatively low expenditure of driving energy, a very fine crushing of various materials such as pigments, or dyestuffs suspended inside a suitable liquid or else granules of cocoa or chocolate and the like.

For a continuous operation, it is necessary to associate a plurality of flat cells of the type referred to having a common horizontal shaft but, by reason of the small size of the balls filling each cell, a difficulty arises in the execution between'the successive cells of a passageway allowing the liquid to be crushed to pass, while arresting the balls.

3,511,447 Patented May 12, 1970 It might be attempted to provide a comparatively fine -meshed sieve for holding the balls back, but experience shows that such sieves are very speedily clogged when operating with a liquid carrying more or less large particles.

According to my invention, the communication between the different cells is ensured by an annular clearance between the common horizontal shaft and the partitions separating the cells, the radial breadth of said clearance being smaller than the diameter of a ball.

Such a clearance may be given a comparatively large surface so as to allow the desired throughput of liquid while braking its passage between two cells with a view to ensuring a satisfactory filling of each cell and an adequate crushing. It is sufiicient for this purpose to give a suitable value to the diameter of the shaft. Although the radial breadth of said clearance is small, the tendency of clogging is cut out since one of the walls of the annular clearance is formed by the shaft and moves thus permanently during the crushing operation, which prevents the formation of a cohesive deposit.

According to a preferred embodiment, the apparatus includes at the inlet of the liquid mass to be crushed and at the outlet of the crushed mass a cell carrying no balls, which allows the inlet or outlet of the mass as the case may be to be provided through an ordinary opening which can without any drawback be given a size larger than the balls and be located at any suitable point suiting the throughput of the apparatus.

The following description and corresponding accompanying drawings given by way of example and by no means in a limiting sense will allow understanding my invention, the features appearing both in the drawings and in the specification forming obviously part of said invention. In said drawings:

FIG. 1 is a horizontal sectional view of a preferred embodiment of my invention FIG. 2 is a detail sectional view through line II-II of FIG. 1 on an enlarged scale The crusher illustrated includes a stationary cylindrical casing 41 enclosed if required within an outer casing 42 so as to form a jacket 43 through which may flow cooling Water or else a heating fluid as in the case of the crushing of molten cocoa or chocolate.

Along the axis of said cylinder there is fitted a shaft 44 revolving Within bearings 45 carried by the corresponding covers 46 of the casing. At one of its ends, the left-hand end in the case illustrated, the shaft 44 extends beyond the cylindrical casing, so as to be coupled with a power unit which is not illustrated and is adapted to drive the shaft into rotation. At its other end, the shaft does not pass through the corresponding cover as illustrated, which cuts out the necessity of fiuidtight arrangements at the corresponding end. Vertical partitions 47 subdivide the inside of the cylinder into a number of cells the breadth of each of which in a direction parallel with the shaft 44 is preferably less than one quarter of the diameter of the cylinder 41 and may in fact be much smaller; consequently, each of the cells enclosed between two successive partitions 47 is of a clearly flat shape. In each of the cells, the shaft 44 carries radial agitating arms 48 which revolve in unison with the shaft and impart horizontal movements in alternating directions to the small balls 54 filling the volume of each cell to the extent of approximately said balls being illustrated only in one of die cells for sake of clarity.

In the example illustrated, two agitating arms 48 are provided in each cell, said arms extending along a common diameter being constituted by a spindle or round bar fitted in a diametrical opening 49 of the shaft 44, and held fast in said opening, for instance by means of a clamping screw 50. The diameter of such a round bar is selected so as to provide the desired stirring of the balls. Said diameter is preferably larger than one half the breadth of each cell, which means of course a suit-. able matching between the three following parameters: diameter of the shaft 44 provided with the openings 49 in which the bars 48 are fitted, diameter of said bars 48 and breadth of the cells. Said matching is an easy matter since it is of interest to arrange the successive partitions 47 near one another and to obtain very flat cells, their breadth being less than A; of the diameter of the cylinder 41, whereas the shaft 44 may be given a large diameter with a view to preventing any objectionable sag of said shaft between the two bearings 45 carrying it. The arms 48 may also be secured to the shaft by screwing into tapped radial openings provided in said shaft.

The partitions 47 separating the different cells are secured to the inner surface of the cylindrical casing 41 and stop inwardly short of the shaft 44, so as to leave between their inner edges and the shaft an annular clearance 51 the annular breadth of which is clearly less than the diameter of a ball. For instance, with balls of a diameter of 2 mm. this radial breadth It may be equal to 1 mm.

The liquid to be crushed progresses between the successive cells through said annular clearances, said liquid being fed into the crusher by a pump, possibly of the variable throughput type, so as to match the desired fineness of crushing. Said liquid enters the cells through a tubular connection 52 extending through one of the covers of the cylinder 41 and escapes after it has been crushed through a further tubular connection 53 provided on the opposite cover. The annular clearances may be given each a suitable cross-section since as already mentioned the diameter of the shaft 44 is comparatively large, of a magnitude of mm. for instance. However, said clearances do not allow the passage of the balls from one cell to the next and consequently each cell retains the volume of balls carried therein, which is important for a proper operation of the machine. Furthermore, since the openings thus designed are bounded to one side by the surface of the shaft 44 which rotates continuously during the crushing operation, no cohesive deposit can form within the opening formed by said clearances, which therefore cannot be clogged in spite of reduced breadth.

Preferably, the first cell, into which the channel 52 feeding liquid to be crushed into the machine opens, carries no balls. It may be given a breadth smaller than that of the following ball-carrying cells. Said first cell may enclose a stirrer 48a which is less thick as compared to the other stirrers 48 and assumes for instance a flat shape. A similar arrangement may be provided at the output end of the apparatus.

There is illustrated in FIG. 1 a screwed plug 47a fitted in one of the cells, the removal of said plug allowing the introduction of balls into said cell and also its emptying after rotation of the crusher through one half revolution. In practice, it is of advantage to provide such a plug for each of the cells.

The operation of the apparatus may be readily understood. The liquid entering at 52 and laden with more or less large particles for instance particles of pigments or of dyestuffs is merely moved and stirred inside the first cell carrying no balls. Its throughput depends on the cross-section of the annular clearances 51 and on the pressure of the pump delivering it into the connection 52. The fluid passing through the first cell enters then the next cell and fills the volume left free by the balls carried by the latter including the gaps between the balls as furthered by the resistance opposed by the losses of head across the annular openings or clearances between the successive cells and also inside said cells by the small balls filling them. The liquid progresses thus from one cell to the next through the annular clearances 51 and fills each of said cells. In each of said cells, the particles suspended in the liquid are crushed by the mutual movements of the balls imparted thereto by the rotary agitating arms 48. The fineness of the crushing is increased from one cell to the next.

By way of example, I may mention that I have designed a crusher with a cylinder 41 of a diameter of 500 mm., said cylinder containing ten ball-filled cells, the breadth of each of which cell was equal to 50 mm. Each cell enclosed a round diametrical arm 48 of a diameter of 28 mm. The volume of each of said ten cells was filled up to by glass balls having a diameter of 2 mm. and said cells communicated through annular clear ances having a radial breadth of /2 mm. while the diameter of the shaft carrying the agitating arms was equal to 60 mm. At the inlet and outlet ends of the cylinder, the latter included also a cell of a breadth of 25 mm. carrying no balls and enclosing a stirrer of a breadth of 10 mm.; the length of the apparatus was thus equal to about 550 mm. Such an apparatus, wherein the shaft carrying the stirrers was driven at a comparatively low speed of a magnitude of to 150 rpm. required a power of only 4 HP, whereas its production, in the case of the crushing of a pigment-carrying paste intended for the production of a paint, was equal to about 200 kgs./ hour, which allows producing 500 kgs. of paint.

My improved apparatus shows thus as an advantage a considerable efliciency with reference to the power consumed. It shows furthermore the advantage of a very small size associated with a low cost price and with a comparatively reduced speed of rotation, which leads to a reduced heating while the crushing is executed down to an excellent grade of fineness. The data just disclosed are given obviously by way of example and by no means in a limiting sense.

In other embodiments of my invention, each flat cell the general design of which is the same as hereinabove is given a diameter of 350 mm. and a breadth of 40 mm. Said cell is provided with a rotary stirrer formed by a diametrical arm of a radius of 11 mm. and a length of 332 mm. The free volume of the cell is filled up to 90% with balls made of hardened glass and having a diameter of 3 mm. The rotary diametrical arm leaves between it and the vertical walls of the cell and also between its ends and the cylindrical wall of the latter gaps equal to 9 mm. which are thus equal each to 3 times the diameter of the balls. Said condition allows obtaining a very fine crushing through a rolling between the balls with reference to one another without any risk of breaking of the latter.

The screwed plug 47a formed on each of the flat cells allows said cells to operate intermittently.

In fact, such a plug allows filling each cell with the liquid to be crushed after which the shaft is caused to revolve with its agitating arms and finally when the operation has lasted a sufficient time, say one half hour, the cells are emptied after rotation of the casing through one half revolution. Of course, when emptying the crusher, it is necessary to insert sieves to replace the plugs so as to prevent the balls from escaping and to allow only the crushed mass to drop out of the machine. It may be of advantage to provide double walls for the vertical covers and partitions of the cells, and also for their cylindrical walls so as to form jackets for the flow therein either of cold water or else of hot water or steam if it is desired to crush the products which are fluid only at a raised temperature, for instance cocoa or chocolate which are fluid at about 60 C.

The cylindrical walls of the cells, the vertical covers, the shaft and the agitating arms may all be made of stainless steel or of a hard alloy steel. For instance, it is possible to use to advantage the steel supplied by Aciries de Pompey, Meurthe-et-Moselle, France, under the designation PM35 and containing: C=0.18%, Mn=l.5%, Cr=1.5%, Mo=0.15%, V=0.10%, P=0.03%. Said steel allows obtaining a hardness of kgs, which in the case of glass balls cuts out substantially in practice any possible wear. Since the agitating arms revolve at comparatively slow speeds, the light colors remain unaltered. It is also possible from this standpoint, to improve the apparatus by coating the partitions 47 separating the cells by means of glass, enamel or ceramic discs, while the agitating arms are constituted by glass bars with carefully rounded ends or else by steel arms coated with glass, enamel or ceramic Ware.

The shaft and cylinder may also be lined with a coat of glass enamel or ceramic ware.

What I claim is:

1. A ball crusher comprising at least one flat unit grinding cell, said at least one cell comprising a cylindrical container having two substantially vertical, spaced end walls and an outer peripheral wall, a rotating shaft substantially perpendicular to said end walls and coaxially disposed with respect to the axis of said container, radially extending agitating arms fixed to said shaft within said container, and a number of balls filling almost all the available space in said container, the axis of each of said agitating arms being disposed in a same radial plane and the interval between each said end wall of said at least one cell and said agitating arms as well as the interval between each free end of said agitating arms and said peripheral wall being equal to approximately a few times the diameter of one of said balls.

2. A crusher as claimed in claim 1 wherein said agitating arms comprise two diametricallyaligned bar members.

3. A crusher as claimed in claim 1 wherein the interval surrounding said agitating arms is equal to approximately three times the diameter of one of said balls.

4. A 'ball crusher as claimed in claim 1 comprising several successive unit grinding cells, each of said several cells comprising vertical, spaced partitions parallel to said end walls and communicating therein between by means of an annular clearance provided between said shaft and said partitions thereby providing a passageway between said successive grinding cells for the material to be crushed, said clearance having a radial breadth which is smaller than the diameter of one of said balls and said agitating arms being disposed for rotation between adjacent ones of said spaced partitions.

5. A ball crusher as claimed in claim 4, which further comprises auxiliary terminal cells at each end of said successive grinding cells, means for feeding the material to be crushed through one of said terminal cells into said successive cells and means for exhausting the crushed material out of said successive cells through the other one of said terminal cells.

References Cited UNITED STATES PATENTS 241,653 5/1881 Harrison 241-153 2,019,454 10/1935 Larsen 241l72 X 2,779,752 1/1957 Vining 241173 3,223,336 12/1965 Wienert 241-172 FOREIGN PATENTS 848,514 9/1960 Great Britain.

ROBERT C. RIORDON, Primary Examiner M. G. RASKIN, Assistant Examiner 

